Looking for something new to do? Try making music on the web. While you do, you'll be stimulating both of the brain's hemispheres - the 'rational' left hemisphere will be analyzing the structure of the music while the 'intuitive' right hemisphere creates the melody. (While many activities engage one side of the brain or the other, scans actually show that music stimulates both hemispheres more than any other activity.) While you're at it, you might even increase the size of your corpus callosum - the canal that ferries information between the two hemispheres and is thought to be larger in musicians! Throw in music's scientifically-proven ability to relax us, as well as its innate appeal to those of us who like math and physics, and what better way to get a workout!
So go ahead and make some music. The following three websites offer free and interactive ways for musicians and non-musicians alike to play:
JamStudio.com ("The On-line Music Factory"):
A fun site with immediate music-to-your-ears gratification - even for those of us who are tonally challenged. Use the intuitive interface to select chords to display in the score, and then select sounds (instruments) to add to the mixer.
You can create a free account for basic membership, but must buy the All Access pass if you decide you actually want to create MP3s and use JamStudio's sounds royalty-free.
noteflight.com ("Reinventing the way that people create, share, and use written music"):
A user friendly on-line resource for writing and sharing notated music, this site was created by a talented group of artist-engineers at Noteflight. (Their bios alone seem to confirm the brain link between math and music.) Create a free account which will allow you to create, edit and save your scores. Use the online library to share your music with the user community as well as to "find, favorite, and comment on" other scores.
Musicalgorithms("An Interactive Exploration of the Relationship between Music and Mathematical Formulas"):
Much heavier on the math-to-music relationship than the other applications, this educational interactive site lets users create musical representations of mathematical models. Type in a sequence (Fibonacci, anyone?) and see what it sounds like.
What I like best about these sites is that you don't need a lot of time or experience to jump in and create some sort of product. And whatever the sound of the outcome, you just gave your brain some heavy lifting.